The Neurobehavioral (NB) Core complements and expands the resource, scientific, and leadership objectives of the HNRC in improving the effectiveness and public health impact of local, national, and international neuroAIDS research. Building on its accomplishments during the prior funding period, the NB Core aims to provide: 1) Performance scores on individual neuropsychological (NP) measures, as well as clinically and objectively derived global and domain-specific ratings of NP functioning;2) global and domainspecific determinations of NP change in individual participants using validated clinical and actuarial methods; 3) consensus diagnoses of HIV-associated neurocognitive disorders;4) self-assessment of cognitive and neuropsychiatric complaints and related difficulties experienced in everyday life;5) current and lifetime history of mood and substance-related diagnoses;6) laboratory-based measures of everyday functioning abilities, including medication management, work-related abilities and automobile driving;and 7) technical assistance, training, certification, consultation, and career development mentoring. The scientific aims of the NB Core include: 1) Advancing scientific knowledge on the nature and extent of the neurobehavioral effects of HIV disease in older adults and adolescents;2) examining the impact of HIV and aging specifically on prospective memory and associated problems in everyday functioning;and 3) facilitating the development and implementation of national and international research efforts regarding the neurobehavioral effects of HIV and disease co-factors. Innovations include: 1) Utilization of paradigms derived from cognitive neuropsychology to elucidate the component processes of cognitive deficits in HIV, which may improve the detection and differential diagnosis of HIV-associated neurocognitive disorders;and 2) Continued development and validation of culturally relevant neurobehavioral instruments, including the generation of normative standards for minority and international populations. In summary, the NB Core enhances the resource, scientific, and clinical relevance of the HNRC by focusing on scientific questions related to the impact of HIV on cognitive, affective, and adaptive functions, which further augments the transdisciplinary aims of scientific Cores that focus on the biologic (e.g., neuropathological) consequences of HIV infection.